The present invention relates to a tow conveyor for moving shopping carts between two different floors of a building. More specifically, the present invention relates to an inclined shopping cart conveyor that can be positioned adjacent to a people-moving escalator such that the shopping cart conveyor moves the shopping carts between two different floors of a building to coincide with the movement of the shoppers.
Currently, most large department stores occupy single floor buildings that include many different product departments and thus have a footprint that covers tens of thousands of square feet. In these large department stores, shoppers typically use shopping carts to carry selected merchandise throughout the store while the shopper continues to select merchandise from the various departments within the store. Since a shopper may be selecting a large number of items having substantial weight, shopping carts are essential in the current department store environment.
Large department stores are most often located in suburban areas where enough land is available to build a store large enough to include all of the merchandise to be offered by the retailer. Thus, many large department store chains have been unable to open stores in large, populated urban areas due to the unavailability of large blocks of single floor retail space. However, in these same urban areas there are often a number of multi-floor vacant buildings that would be large enough to accommodate the floor space required by the department store. Department stores are unable to utilize these multi-floor buildings due to the inability of the department store to transport shopping carts between the various floors of a multi-level store. Although elevators can move shopping carts between the various floors of a multi-floor store, elevators are unable to handle the large number of consumers typically found in one of the large chains of department stores.
Therefore, a need clearly exists for a method of moving shopping carts between various floors of a multi-level department store. Further, a need exists for a system for moving shopping carts along with or simultaneously with the movement of a shopper between the same floors of a department store.
The present invention relates to an inclined tow conveyor for transporting loaded or unloaded shopping carts between floors of a building. The inclined conveyor of the present invention is constructed to be positioned and used along side a conventional, people-moving escalator such that shopping carts can be loaded onto the inclined shopping cart conveyor and transported along side the shopper who is using the shopping cart.
The inclined shopping cart conveyor of the present invention extends between a loading end and an unloading end. When the inclined conveyor is configured to be an upwardly moving conveyor, a shopping cart is received at the loading end on a lower floor. The shopping cart is received by a continuous conveyor assembly that engages a front portion of the shopping cart and transports the shopping cart upward along the inclined conveyor to the unloading end on an upper floor.
The inclined shopping cart conveyor includes a front wheel track and a rear wheel track that guide the front and rear wheels, respectively, of the shopping cart along the inclined conveyor as a result of the engagement of the shopping cart with the continuous conveyor assembly. The continuous conveyor assembly includes a continuous conveyor belt having a series of spaced drive lugs. Each of the spaced drive lugs positively engages a portion of an engagement bracket mounted near the front end of the shopping cart. In the preferred embodiment of the invention, the engagement bracket includes a generally horizontal cross bar that contacts one of the drive lugs mounted to the conveyor belt. Upon reaching the upper floor, the shopping cart is discharged from the inclined conveyor and can be retrieved by the shopper.
The inclined shopping cart conveyor of the present invention preferably includes an infrared or heat sensor mounted above the loading end of the inclined conveyor. The infrared sensor is positioned to detect whether a person has passed beneath an entry arch positioned at the loading end of the conveyor. The infrared sensor is coupled to a control unit that terminates the movement of the conveyor belt upon detection of a person. In this manner, the control unit of the inclined conveyor prevents operation of the conveyor when a person is too close to the moving conveyor belt.
The inclined conveyor further includes a pair of spaced photoelectric sensors positioned near both the loading end and the unloading end of the inclined conveyor. The photoelectric sensors are each coupled to the control unit of the inclined conveyor. The photoelectric sensors are spaced from each other by a large enough distance such that a shopping cart does not simultaneously break the through beams generated by a pair of spaced sensors. Thus, during normal operation when only a shopping cart is being loaded onto the inclined conveyor, the photoelectric sensors will permit continued operation of the inclined conveyor. However, if both photoelectric sensors are tripped at the same time, the control unit will interrupt operation of the inclined conveyor. Again, the photoelectric sensors prevent operation of the inclined conveyor when a person is present at either the loading end or the unloading end of the inclined conveyor.
The inclined conveyor of the present invention includes a jam detector that senses when one of the shopping carts is jammed along the length of the inclined conveyor. In the preferred embodiment of the invention, the jam detector includes a pair of metallic conductor strips that extend along the length of the inclined conveyor and are positioned slightly above the moving conveyor belt. One of the metallic conductor strips receives an electric charge and both of the conductor strips are connected to the control unit of the inclined conveyor. When a jam occurs along the length of the inclined conveyor, a metallic cross bar attached to the front end of the cart completes an electrical connection between the spaced metallic conductor strips. The contact between the shopping cart and the metallic conductor strips is sensed by the control unit. Upon sensing a jam, the control unit initially terminates operation of the drive motor that is moving the conveyor belt. Preferably, the control unit then reverses the direction of operation of the drive motor in an attempt to clear the jam along a length of the inclined conveyor. If the jam is cleared, the conveyor resumes normal operation. However, if the jam is not cleared, the control unit suspends operation and must be manually reset.
The upwardly moving inclined conveyor includes a plurality of cart arrestors positioned along the length of the conveyor. Each of the cart arrestors is operable to prevent the uninhibited downward movement of a shopping cart should the shopping cart become disengaged from the conveyor belt. Each of the cart arrestors includes a spring-biased stopping arm that allows the cart to move freely in the upward direction, while preventing the uninhibited movement in the downward direction.
The downwardly moving inclined conveyor also includes a plurality of spaced cart arrestors. In the downwardly moving conveyor, each of the cart arrestors includes a stopping arm that extends into the path of travel of the shopping cart. Upon detecting a cart moving at the proper speed, the control unit of the inclined conveyor retracts a solenoid to pull the stopping arm inward and out of the path of the shopping cart. However, if the control unit does not activate the solenoid, the stopping arm prevents the downward movement of the shopping cart. Thus, the control unit must positively activate the solenoid in order to allow the shopping cart to move past the cart arrestor.
The inclined conveyor additionally includes a front wheel alignment and turning system for orienting the front wheels of the shopping cart in a common position in order to prevent unnecessary operation of the jam detector along the conveyor belt. The front wheel alignment system includes a pair of spring biased turning mechanisms for rotating one or both misaligned front wheels through 180 degrees. The turning mechanism provides that leading edges of the front wheels are positioned behind the front end of the shopping cart with the horizontal cross bar on the shopping cart remaining positioned slightly above the lowermost portion of each front wheel. With this arrangement, the shopping carts will move smoothly along the conveyor without contact between the shopping cart cross bar and the conductor strips of the jam detector at the point where the conveyor belt angles away from the horizontal.
The inclined conveyor further includes a cart travel correction device for maintaining proper engagement between the shopping cart cross bar and a drive lug on the moving conveyor belt. The correction device includes a pair of spaced rods which are fixedly positioned slightly above the moving conveyor belt and disposed generally perpendicularly to the direction of cart travel. Normally, as the shopping cart moves along the loading end, the cart cross bar engages one side of a moving drive lug. However, in the event the cart cross bar rides upon an uppermost surface of the moving drive lug, the cart cross bar will engage the fixed rods, moving the cross bar to the proper position on a subsequent drive lug so that the cart will continue to travel smoothly along the inclined conveyor.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.